The case
I build my own case/box to house my PA . I used hook profiles from the store and got some 2mm thick aluminum plate. I made all panels custom made. It is very sturdy and also a bit heavy, but its ok. A bit of black primer and nice gray paint, and the box looks ok.
The filter is on top of the PA. I connected the PA, the filter and the back panel via flat cable. On the Arduino I put an extra 10nF capacitor on all inputs !! To make sure the Arduino is not suffering from the high power. I needed a LOT OF holes to get enough ventilation. Two fans of 12V 160 mW is not enough. I am looking for some bigger flow. Two additional fans on the back? I have not decided yet,......
It is now Aug 1 and I decided how to cool the PA. I drilled a whole bunch of holes in the bottom of the case, just above the PA PCB. I put the Case on rubber feet at least one cm high, better two. Than I placed two 370 mA fans on to the bottom of the case just above the holes. Than on top of that I put the PA PCB and on top of that the Filter PCB. At both sides of the cooling block, I suck away the warmed air to the front and the back of the Case, via again a lot of drilled holes.
I leaded the flat cables close to the aluminum, and at the entry in the Arduino compartment, a ferrite block is added, to be sure.
A few other tips:
I used two 30 Ampere plugs for the 50V entrees. And thick cable to the Power Supply (at least 1.5 mm2). Twist the power cable all the way to the PS to make sure as little HF power is picked up. I also added a ferrite core (cable two times around the cable, not more !!!! otherwise you create a resonating circuit around 14 MHz. Maybe better is only one time, to be safe for higher frequencies.
I used two simple meters to show me the input power, the output power and the reflected power. 4 little green LEDs to show me the band code of the FT-950. A TX and a RX LED and a panic LED (big one). For more info I use a 4x16 character cheap display which is commonly used with an Arduino.
I also have a switch to enable the transceivers INH (inhibit transceiver) to emulate transmitting without input power. The INH is also used by the Arduino to stop power input in case of emergencies, and for the correct timing of the RX/TX relays. To make sure no input power is coming if you are just switching the relays.......make a RX-TX process description how to steer all the ins and outs.
I added a ant1 - ant2 switch, a screen switch off switch, a test mode switch and a lin/log switch for reading out the gauges. Finally two switches under the gauges for switching between Pin and Pout (gauge 1) and SWR/Preflected (gauge two). And,.....an arduino reset button, which we will never use of course,....HI.
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